NCRIS Groundwater Infrastructure

North Stradbroke Island

Where is North Stradbroke Island?

North Stradbroke Island is a large sand-mass island around 10 km off the coast, east of Brisbane. It is around 400 km2 in area with sand masses up to 250 m high and is located close to the margin between temperate and subtropical climate zones. Mean rainfall is around 1500 mm. The large, aeolian dunes date from the Quaternary, with older dunes and buried soils in the west and younger dunes towards the eastern side of the island. Groundwater-fed water bodies (e.g., lakes, springs, wetlands) and their associated groundwater-dependent ecosystems are common features of these sand masses. Many of the lakes have significance to local indigenous communities.

Why is this location important?

Like other important sand mass systems in south-east Queensland, North Stradbroke Island contains significant groundwater resources which are accessed by local communities and mining companies. In addition, a significant volume of groundwater is exported to the mainland. While there is the potential for expanded groundwater use, so little is known about groundwater-dependent water bodies and ecosystems that expansion is suspended. Dependent ecosystems include freshwater and estuarine wetlands, mangrove and paperbark communities, and surface-water fauna. There is evidence that vegetation communities have been changing response to changing groundwater conditions. Several species are listed nationally as endangered and a number are endemic to the island.

More generally, a better understanding of coastal hydrological and ecohydrological rocesses is required to optimally manage coastal groundwater systems. A coastal Super Science site delivers the opportunity for developing long term understanding of hydrological processes and dependencies in these critical groundwater environments. Given the wide range of water management and scientific issues arising from rapid development and the threat of climate change impacts, North Stradbroke Island in south-east Queensland is a good location, having hydrological features representative of many coastal groundwater systems around Australia.